South Carolina followed, representing the South. Nevada had been promised the fourth early slot for the West.

But Florida had other plans and scheduled its primary on January 31, thereby jumping in front of Nevada's February 4 caucus.

Iowans, lacking a favorite son or candidate from a neighboring state, split their vote between the national frontrunner Mitt Romney and Rick Santorum, who had moved his family to Iowa last summer and campaigned there on an almost full-time basis. Newt Gingrich ran a poor fourth in the Hawkeye State.

New Hampshire gave an overwhelming victory to Romney, who served as a popular governor in next door Massachusetts and owns a family home in the Granite State.

Gingrich finished fifth there. Many pundits discounted the Romney New Hampshire win based on his perceived "home field" advantage.

As the campaign moved south, Gingrich found his footing. Gingrich has spent 40 years as a Republican leader in South Carolina's Southern neighbor, Georgia.

Gingrich was a GOP office holder in the region during a time when Republican elected officials were exceedingly rare. Not surprisingly, he had a victory in South Carolina that mirrored Romney's win in New Hampshire.

Like South Carolina, Florida also shares a border with Gingrich's home state. Commentators note that Florida has become more cosmopolitan over the past two decades.

Of course, so have South Carolina and Georgia. Yet, they remain Southern in character.

Southerner Gingrich, who understands the culture and politics of the South, will do well – and could still even win – in Florida. (Although the most recent polls show that Romney appears to be pulling away in the Sunshine State.)

The fact that New Englander Romney finished second in South Carolina and leads in Florida foreshadows his strength as a national candidate.

Gingrich's poor showings in Iowa and New Hampshire indicate the opposite for him.

So far, Gingrich has been lucky: for three weeks, the GOP nominating process and half of the early primaries will have taken place in his backyard.

The month of February will, however, slow any Gingrich momentum gained from strong finishes in the South and may even expose his candidacy as having little more than regional appeal.

He will wait for over a month until Southern states reappear on the calendar. Here's a look at what's ahead after Florida:

Nevada. On February 4, Nevada will hold its caucuses. Romney dominated the caucuses in 2008, when he garnered 51% of the vote in a seven-person race. He should do very well there this time around, as Nevadans remember Romney's turnaround of the Salt Lake City Winter Olympic Games in neighboring Utah. Further, as one of only two states with two Mormon U.S. Senators (one a Republican and one a Democrat), Romney's religion will be an advantage rather than a hurdle in the Silver State. Expect a solid Romney win in Nevada.

Maine. Maine’s week-long caucuses run from February 4 through 11, with results to be reported on the 11th. In 2008, Romney won in Maine with 52% of the vote. Like Nevada, the Romney campaign has been organizing in Maine for months. Expect the Pine State voters to reward a fellow New Englander with a big win.

Missouri. The Show Me State holds its non-binding primary on February 7. Border state Missouri might have been hospitable to the Georgian candidate, but Gingrich failed to file for the primary and will not be on the ballot. Whether this was due to incompetence or strategy (Gingrich claims he is skipping the election due to the primary's non-binding status), Missourians will not appreciate the slight. It might be very difficult for Gingrich to rebound among Missouri Republicans when they hold their binding caucuses on March 17. Further, Romney locked up early endorsements from U.S. Senator Roy Blunt, former Senator Jim Talent and Missouri's popular State Auditor, Tom Schweich. With Gingrich off the ballot, Santorum (assuming he is still in the race) will seek to make a stand here as the conservative alternative to Romney. Missouri's primary could be an important “momentum moment” for Romney.

Minnesota. Minnesota will also caucus on February 7. Romney beat McCain by a 2 to 1 margin in the North Star State in the last cycle. Given that Minnesota's popular former Governor Tim Pawlenty is one of Romney's most effective surrogates and that the Romney campaign is known for its caucus prowess, a Romney win here is likely.

Colorado. Colorado will share the stage with Missouri and Minnesota on February 7. It has the potential for being a Gingrich bright spot in what otherwise could be a tough month. Romney won the state in 2008 by a big margin, but this year, Gingrich maintains a strong lead in a month-old poll. Such polling data and the state's large number of evangelical voters will make it an attractive target for both Gingrich and Santorum.

Arizona. Two weeks later, the Grand Canyon State holds its primary on February 28. Romney ran a strong second to home state Senator John McCain in Arizona's 2008 primary. This time around, McCain is campaigning hard for his former rival. Romney also has the endorsement of Tea Party favorite and U.S. Senate Candidate, Congressman Jeff Flake. Like Intermountain and Western states Nevada, Idaho and Utah, Arizona looks like very friendly territory for Romney in 2012.

Michigan. Michiganders also cast their ballots in a primary on February 28. The Wolverine State gave Romney his biggest win in 2008, keeping him in the race after Huckabee and McCain won in Iowa and New Hampshire, respectively. Romney is a Detroit native and grew up in Bloomfield Hills. His late-father, George, was a popular three-term Governor and he still has siblings and cousins in the state. Assuming he remains in the contest, Santorum's industrial state roots and blue collar appeal could make him a contender. Nevertheless, Michigan should be Romney country in 2012.

February’s line up, which on its face, hospitable geography for Romney, is not Gingrich's only concern next month.

The Nevada, Maine, Minnesota and Colorado contests are caucuses, not primaries.

Ron Paul’s well-organized and highly-motivated volunteers have been organizing in these states since 2008, with the hope of winning at least one of them for their candidate. As in Iowa, Paul will certainly do well in the caucuses. In addition to his certain loss in the Missouri primary, Gingrich could finish third in a number of the caucus states.

Gingrich has made the best of the stage provided by the numerous televised GOP debates to-date and Sheldon Adelson’s generosity. But his real advantage so far has been his status as essentially a “favorite son” candidate in two of the first four GOP contests.

He will now be severely challenged by the primary geography of the contests in February. It is unclear if his candidacy can weather the month.

Robert C. O'Brien is a partner in a national law firm in Los Angeles. He served as a U.S. Representative to the U.N. and advises Republican presidential candidate former Mitt Romney on foreign policy. The views herein are his own. Robert’s website is: www.robertcobrien.com and follow him on Twitter@robertcobrien.

Robert C. O'Brien is a partner in a national law firm in Los Angeles. He served as a U.S. Representative to the U.N. and advised Republican presidential candidate Governor Mitt Romney on foreign policy matters. Robert's website is www.robertcobrien.com. Follow him on Twitter @robertcobrien.